Apparatus and method for encapsulating tritium

Abstract

A module comprising: one or more vials containing tritium; one or more tritium covers; and an open space within the one or more tritium covers, wherein the one or more vials containing tritium are located within the open space of the one or more tritium covers so that the one or more tritium covers protect the one or more vials containing tritium, and wherein the one or more tritium covers are made from a material that exhibits sufficient strength so that the module protects the one or more vials containing tritium from damage when dropped from a distance of 1 m or more.

The invention claimed is: 
     
       1. A knife comprising:
 a handle including a handle length extending between a proximal end and a distal end, the handle including a handle thickness extending between a first side and an opposing second side, the handle including a through-hole extending through the handle thickness and between the proximal and distal edges; 
 a blade connected to the handle, the through-hole extending through the blade; and 
 a module placed into the through-hole so that an outer surface of the module is generally flush with the first side and the opposing second side of the handle, the module comprising:
 one or more vials containing tritium; 
 a tritium holder including one or more planar surfaces, the one or more planar surfaces are located generally parallel to the first side of the handle, the second side of the handle, or both, the tritium holder including a cradle outwardly extending from one of the one or more planar surfaces, the cradle supporting opposing ends and an elongated surface of one of the one or more vials containing tritium; 
 pair of dome-shaped, discrete, and transparent tritium covers surrounding the tritium holder, each of the pair of tritium covers including an outer surface defining the outer surface of the module; and 
 an open space defined between one of the one or more planar surfaces of the tritium holder and an inner surface of a corresponding one of the pair of tritium covers, the inner surface being generally parallel to the outer surface of the tritium covers and generally parallel to the planar surface, the cradle supporting the vial containing tritium being located in the open space so that the pair of tritium covers protect the vial containing tritium, and 
 wherein the pair of tritium covers are made from a material that exhibits sufficient strength so that the module protects the one or more vials containing tritium from damage when dropped from a distance of 1 m or more, 
 wherein an elongated portion of the one or more vials containing tritium are visible from the first side and the opposing second side of the handle. 
 
 
     
     
       2. The knife according to  claim 1 , wherein each of the pair of tritium covers have two or more of the following properties:
 high transparency, wherein the light transmission is in the range of about 80% or greater in the visible light range; 
 high resistance to chemicals, wherein the high resistance to chemicals includes resistance towards polar media, non-polar media, or both; 
 high impact resistance, wherein the impact resistance is measured using Charpy impact notched, and the results are in the range of about 10 kJ/m 2  or greater; 
 high resistance to stress cracking, wherein the flexural stress is in the range of about 10 MPa or greater in polar media and non-polar media; 
 high heat deflection temperature, wherein the beat deflection is in the range of about −40° C. and about 82° C.; and 
 low water absorption, wherein the water absorption is measured using a saturation point, and the results are in the range of about 3.0% or lower. 
 
     
     
       3. The knife according to  claim 1 , wherein each of the pair of tritium covers are made from a material with a sufficient glass transition temperature so that the tritium covers protect the one or more vials containing tritium from breaking when exposed to a temperature shock. 
     
     
       4. The knife according to  claim 1 , wherein the module has sufficient Shore D hardness so that the module is resistant to physical impact, cracking, shattering, or a combination thereof. 
     
     
       5. The knife according to  claim 1 , wherein the pair of tritium covers are attached to each other with an adhesive sealant so that the module is substantially fluid resistant. 
     
     
       6. The knife according to  claim 1 , wherein the pair of tritium covers are bonded to the tritium holder forming the module, and the module is sufficiently secure so that the one or more tritium vials within the pair of tritium covers are protected from fluid penetration, physical impact, cracking, shattering, chemicals, temperature shock, or a combination thereof. 
     
     
       7. The knife according to  claim 1 , wherein the tritium holder includes one or more grooves to improve the bonding between the tritium holder and the pair of tritium covers. 
     
     
       8. The knife according to  claim 1 , wherein the one or more vials containing tritium are bonded to the one or more cradles so that the one or more vials containing tritium are prevented from shifting vertically, horizontally, diagonally, rotationally, or a combination thereof during impact. 
     
     
       9. The knife according to  claim 1 , wherein the module further comprises voids, holes, through-holes, recesses, or a combination, thereof, so that the module may be attached to the knife;
 the handle including a handle length extending between a proximal end and a distal end, the handle including a handle thickness extending between a first side and an opposing second side, the handle including a through-hole extending through the handle thickness and between the proximal and distal edges. 
 
     
     
       10. An article of manufacture comprising:
 a handle including a handle length extending between a proximal end and a distal end, the handle including a handle thickness extending between a first side and an opposing second side, the handle including a hole extending between the proximal end and the distal end, the hole also extending through the first side, the opposing second side, and a top side of the handle; 
 a module placed into the hole so that a first outer side surface of the module is generally flush with the first side, a second outer side surface of the module is generally flush with the opposing second side of the handle, and an outer top surface of the module is generally flush with the top side of the handle, the module comprising:
 one or more vials containing tritium; 
 a tritium holder including a planar surface and one or more cradles extending outwardly from the planar surface, each cradle supporting opposing ends and an elongated surface of one vial containing tritium; 
 a transparent dome-shaped tritium cover engaging at least a portion of the planar surface of the tritium holder, the tritium cover including an outer surface defining the outer top surface of the module; and 
 an open space defined between the planar surface and an inner surface of the tritium cover, the inner surface being opposite the outer surface of the tritium cover, the one or more cradles and the one or more vials containing tritium are located in the open space, 
 wherein the one or more vials containing tritium are located within the open space so that the tritium cover protects the one or more vials containing tritium, and 
 wherein the tritium cover is made from a material that exhibits sufficient strength so that the module protects the one or more vials containing tritium from breaking when dropped from a distance of 1 m or more; 
 wherein an elongated portion of the one or more vials containing tritium are visible from the first side, the opposing second side, and the top side of the handle. 
 
 
     
     
       11. An article of manufacture according to  claim 10 , wherein the article of manufacture is a knife having a folding blade, a tool, a flashlight, a utensil, a shovel, a screwdriver, a hammer, an ice ax, a gripping portion of a tool, or a combination thereof. 
     
     
       12. An article of manufacture according to  claim 10 , wherein the tritium cover has two or more of the following properties:
 high transparency, wherein the light transmission is in the range of about 80% or greater in the visible tight range; 
 high resistance to chemicals, wherein the high resistance to chemicals includes resistance towards polar media, non-polar media, or both; 
 high impact resistance, wherein the impact resistance is measured using Charpy impact notched, and the results are in the range of about 10 kJ/m 2  or greater; 
 high resistance to stress cracking, wherein the flexural stress is in the range of about 10 MPa a or greater in polar media and non-polar media; 
 high heat deflection temperature, wherein the heat deflection is in the range of about −40° C. and about 82° C.; and 
 low water absorption, wherein the water absorption is measured using a saturation point, and the results are in the range of about 3.0% or lower. 
 
     
     
       13. A method comprising:
 providing an instrument including a handle including a handle length extending between a proximal end and a distal end, the handle including a handle thickness including a first side and an opposing second side, and a through-hole extending through the first side to the opposing second side and between the proximal and distal edges; 
 providing a first tritium vial and a second tritium vial; 
 injection molding a first transparent tritium cover and a second transparent tritium cover, each tritium cover having a dome shape and including an outer surface and an opposing inner surface; 
 injection molding a tritium holder having a first planar surface and a first cradle extending from the first planar surface, and a second planar surface and a second cradle extending from the second planar surface, 
 wherein the first planar surface and the second planar surface are generally parallel to one another, 
 bonding the first tritium vial to the first cradle and the second tritium vial to the second cradle; 
 positioning the tritium holder between the first tritium cover and the second tritium cover, 
 bonding the first tritium cover to the second tritium cover so that the first tritium vial is located within an open space defined between the first planar surface and the inner surface of the first tritium cover, and the second tritium vial is located within an open space defined between the second planar surface and the inner surface of the second tritium cover; and 
 inserting the bonded first and second tritium covers into the through-hole so that a shoulder of the first tritium cover engages a corresponding shoulder in the handle, and a shoulder of the second tritium cover engages a corresponding shoulder in the handle, and 
 wherein after inserting the bonded first and second tritium covers into the through-hole, an elongated portion of the first tritium vial is visible from the first side and an elongated portion of the second tritium vial is visible from the second side. 
 
     
     
       14. The method of  claim 13 , wherein the method includes the steps of:
 bonding the first tritium vial to the first cradle with an adhesive sealant and the second tritium vial to the second cradle with the adhesive sealant; and 
 inserting the bonded first and second tritium covers and tritium holder into the through-hole so that an outer surface of the first tritium cover is generally flush with the first side and an outer surface of the second tritium cover is flush with the opposing second side of the handle. 
 
     
     
       15. The method of  claim 14 , wherein the method includes a step of pretreating a surface of the tritium holder, the first tritium cover, the second tritium cover, the first tritium vial, the second tritium vial, or a combination thereof, with a primer or corona treatment. 
     
     
       16. The knife according to  claim 1 , wherein the one or more planar surfaces comprise a first planer surface and a second planar surface that is generally parallel to the first planar surface, the first planar surface includes a first cradle of the at least one cradle, and the second planar surface includes a second cradle of the at least one cradle, the first cradle supporting opposing ends of a first vial containing tritium, and the second cradle supporting opposing ends of the second vial containing tritium.